What to count as CD1?

I started Metformin and Spironolactone two weeks ago. I have been spotting for 8 days and I thought yesterday was going to be the start of my period because it got a little heavier but then stopped in the evening. My doctor said the first day of my cycle is the first day of flow that I need a pad or a tampon. The last 8 days I have only needed a small liner. It is day 96 of my cycle. Should I count the first day of spotting as the start of the next cycle or just continue counting on my current cycle?